Robert the Robot is an android from the Supermarionation television series Fireball XL5, and co-pilot of the craft of the same name. Robert is a valuable part of the World Space Patrol, and the Earth's most advanced robot.
Robert is notable in being made out of a transparent material, allowing the viewer to see its internal workings. Besides being transparent, it also somehow has what humans would call "feelings" or "emotions", and it can become offended or confused rather easily, often resulting in it literally steaming from anger or confusion.
Behind the scenes
The character of Robert is unique in all of the history of Gerry Anderson productions in that Gerry Anderson himself provided the voice with the aid of an artificial larynx.
Robert was also one of the most difficult marionettes to control due to its light weight.